linux双网卡绑定

软硬件环境

• centos

前言

bonding的作用是把多块网卡虚拟成一块网卡，使用一个IP地址，一个MAC地址。一般的发行版内核都支持bonding，如果碰到不支持的，重编下内核使其支持就可以了。

实践

cd /etc/sysconfig/network-scripts
cp ifcfg-eth0 ifcfg-bond0

编辑ifcfg-bond0

# Broadcom NetXtreme II BCM5708 Gigabit Ethernet       
DEVICE=bond0       
BROADCAST=192.168.0.255       
HWADDR=00:22:19:CD:CD:44       
IPADDR=192.168.0.251       
NETMASK=255.255.255.0       
ONBOOT=yes       
GATEWAY=192.168.0.1       
TYPE=Ethernet

ifcfg-eth0配置文件

# Broadcom NetXtreme II BCM5708 Gigabit Ethernet       
DEVICE=eth0       
HWADDR=00:1A:64:64:6C:C8       
NETMASK=255.255.255.0       
ONBOOT=yes       
TYPE=Ethernet

ifcfg-eth1配置文件

# Broadcom NetXtreme II BCM5708 Gigabit Ethernet       
DEVICE=eth1       
HWADDR=00:1A:64:64:6C:CA       
NETMASK=255.255.255.0       
ONBOOT=yes       
TYPE=Ethernet

编辑/etc/modprobe.conf文件

alias bond0 bonding       
options bond0 miimon=100 mode=1      
alias scsi_hostadapter mptbase       
alias scsi_hostadapter1 mptscsih       
options lnet networks=tcp0

开机启动编辑/etc/rc.local文件

modprobe bonding
ifenslave bond0 eth0 eth1

在主备模式下工作，会按照先后顺序提供网卡服务，这里是eth0然后是eth1，如果其中有一块网卡失效，网络也不会中断，这有点像RAID1的功能。一切设置完毕后，重启系统查看配置结果。

ifconfig

bond0     Link encap:Ethernet  HWaddr 00:1A:64:64:6C:C8  
          inet addr:192.168.0.251  Bcast:192.168.0.255  Mask:255.255.255.0
          inet6 addr: fe80::21a:64ff:fe64:6cc8/64 Scope:Link
          UP BROADCAST RUNNING MASTER MULTICAST  MTU:1500  Metric:1
          RX packets:17066 errors:0 dropped:0 overruns:0 frame:0
          TX packets:105 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:1118781 (1.0 MiB)  TX bytes:21938 (21.4 KiB)

eth0      Link encap:Ethernet  HWaddr 00:1A:64:64:6C:C8  
          inet6 addr: fe80::21a:64ff:fe64:6cc8/64 Scope:Link
          UP BROADCAST RUNNING SLAVE MULTICAST  MTU:1500  Metric:1
          RX packets:8672 errors:0 dropped:0 overruns:0 frame:0
          TX packets:89 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:568833 (555.5 KiB)  TX bytes:17518 (17.1 KiB)
          Interrupt:3 Memory:ce000000-ce012100 

eth1      Link encap:Ethernet  HWaddr 00:1A:64:64:6C:C8  
          inet6 addr: fe80::21a:64ff:fe64:6cc8/64 Scope:Link
          UP BROADCAST RUNNING SLAVE MULTICAST  MTU:1500  Metric:1
          RX packets:8394 errors:0 dropped:0 overruns:0 frame:0
          TX packets:16 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:549948 (537.0 KiB)  TX bytes:4420 (4.3 KiB)
          Interrupt:10 Memory:ca000000-ca012100

从上面的输出可以看到,bond0、eth0、eth1的HWaddr都是00:1A:64:64:6C:C8。

查看bonding的状态

cat /proc/net/bonding/bond0

Ethernet Channel Bonding Driver: v3.1.2 (January 20, 2007)

Bonding Mode: fault-tolerance (active-backup)
Primary Slave: None
Currently Active Slave: eth0
MII Status: up
MII Polling Interval (ms): 100
Up Delay (ms): 0
Down Delay (ms): 0

Slave Interface: eth0
MII Status: up
Link Failure Count: 0
Permanent HW addr: 00:1a:64:64:6c:c8

Slave Interface: eth1
MII Status: up
Link Failure Count: 0
Permanent HW addr: 00:1a:64:64:6c:ca